Design and Implementation of a Students’ Information Management System Based on Data Warehouse

近年来，随着学校招生规模的不断扩大，学生的人数越来越多，需要管理的各种学生信息也在不断的增加。所以，基于传统数据库的学生信息管理系统已经不能应对不断变化的信息需求，从而提出了基于数据仓库的学生信息管理系统。基于数据仓库的学生信息管理系统不仅解决了系统的不断扩展性，而且也为决策人员提供了很好的分析功能。 论文首先介绍了基于数据仓库的学生信息管理系统设计和数据分析的研究背景、国内现状和意义，明确了该系统的设计要实现的目标，并进行了可行性分析，提出了系统的构架；其次，进一步对系统进行了详细的需求分析，包括系统需求描述、用户角色分析、系统工作流程等；再次，采用面向对象的分析和设计方法，对该系统进行了...In recent years, with the increasing enrollment scales in universities, the need to manage all sorts of students' information is also in constant increase. So, based on the traditional database students' information management system have already can't cope with changing information needs, thus proposed based on data warehouse students' information management system. Based on data warehouse studen...学位：工程硕士院系专业：软件学院_工程硕士(软件工程)学号：X200923009

Soil heterotrophic respiration in Casuarina equisetifolia plantation at different stand ages

以中国亚热带木麻黄沿海防护林为研究对象,在2006年5月-2007年4月,利用lI-8100土壤呼吸自动观测系统对不同林龄(幼林、中林、成林)木麻黄人工林生态系统的土壤异养呼吸特征进行了监测。结果表明,不同林龄木麻黄林地土壤异养呼吸季节动态均呈单峰曲线,最大值出现在6~7月份,最小值则出现在12~1月份。土壤温度和水分对土壤异养呼吸的季节变化存在显著影响,并有明显的交互作用,进行单因素方差分析发现,土壤异养呼吸季节变化与5CM深的土温存在着较好的指数相关关系(P成林>幼林。随着林龄的增大,土壤异养呼吸对土壤温度的敏感性增强。土壤异养呼吸对土壤总呼吸的贡献在幼林、中林、成林中分别达到71.89%、71.02%和73.53%。幼林、中林、成林样地土壤异养呼吸CO2年释放量分别为29.072、38.964和30.530T·HM-2·A-1。The soil respiration rates (Rh) in 6-year-old (young), 17-year-old (middle-age), 31-year-old (mature) Casuarina equisetifolia coastal plantations were measured using an LICOR-8100 automated soil CO2 flux system from May 2006 to April 2007.Results show that Rh displayed an obvious seasonal pattern across the observed years.The maximum values of Rh occurred at June and July and the minimum at December and January.Soil temperature and soil moisture as well as their interaction had significant effects on the monthly dynamics of Rh.The analysis by one-way ANOVA showed that Rh had a significantly exponential relation (pmature plantation>young-age plantation.With the increase of growth age of plantation, the Q10 of Rh increased.The contribution of Rh to total soil surface CO2 flux was 71.89%, 71.02% and 73.53% for the young, middle-age and mature plantation, respectively.It was estimated that the annual CO2 fluxes from Rh were 29.07, 38.964 and 30.530 t·ha-1·a-1 for the young, middle-age and mature plantation, respectively.supportedbyKeyProjectsintheNationalScience&TechnologyPillarProgramduringtheEleventhFive-yearPlanPeriod(Nos.2006BAD03A14-01);ImportantScience&TechnologySpecificProjectsofFujianprovince(2006NZ0001-2);supportedbytheKeyLaboratoryofsouthmountaintimberculti-va

Novel System of Direct Methanol Fuel Cell Anode Catalysts: NanoTiO_2-CNT-PtNi Complex Catalysts

采用电合成前驱体Ti(OEt)_4直接水解法和电化学扫描电沉积法制备纳米TiO_2-CNT-PtNi复合纳米催化剂.透射电镜(TEM)和X射线衍射(XRD)测试结果表明,纳米PtNi合金粒子(平均粒径8nm)均匀地分散在纳米TiO2-CNT复合膜的三维网络结构中.通过暂态电化学方法研究表明,复合纳米催化剂的电化学活性比表面积为90m~2/g,对甲醇氧化具有很高的电催化活性和稳定性,常温常压下甲醇氧化峰电位为0.67和0.44V,当温度为60℃时,氧化峰电位负移至0.64和0.30V,氧化峰电流密度高达1.38A/cm~2.复合纳米催化剂对甲醇电氧化的高催化活性和稳定性可归因于多元复合纳米组分的协同催化作用,这种作用导致CO在复合纳米催化剂上的弱吸附,从而避免了催化剂的中毒.The nanoTiO2-CNT-PtNi complex catalysts were prepared by the direct hydrolysis of electro-synthetic precursor Ti(OEt)4 and electrochemical scan electrodepositing method. The results of XRD and SEM show that the PtNi nanoparticle of average size 8 nm was dispersed uniformly on nanoTiO2-CNT com-plex film surface. The electrocatalytic activity of the nanoTiO2-CNT-PtNi complex catalysts was investi-gated by cyclic voltammetry and chronopotentiogram. The results indicated that the nanoTiO2-CNT-PtNi complex catalysts with Pt loading of 0.32 mg/cm2 exhibited high electrochemically active surface area of 90 m2/g and very high electrocatalytic activity and stability for electro-oxidation of methanol. The oxidation peak potential of methanol was 0.67 and 0.44 V at room temperature in atmosphere pressure, respectively, and shifted to 0.64 and 0.30 V at 60 ℃ and the oxidation peak current of methanol was 1.38 A/cm2. The high electrocatalytic activity and good stability can be attributed to the synergistic catalytic effect of nano-composite, which leads to the weak adsorption of CO on complex nanostructure catalysts, avoiding poison-ing of the catalysts.国家自然科学基金(No.20476001);; 安徽省自然科学基金(No.00045317)资助项目

Novel system of direct methanol fuel cell anode catalysts: NanoTiO(2)-CNT-PtNi complex catalysts

The nanoTiO(2)-CNT-PtNi complex catalysts were prepared by the direct hydrolysis of electrosynthetic precursor Ti(OEt)(4) and electrochemical scan electrodepositing method. The results of XRD and SEM show that the PtNi nanoparticle of average size 8 nm was dispersed uniformly on nanoTiO(2)-CNT complex film surface. The electrocatalytic activity of the nanoTiO(2)-CNT-PtNi complex catalysts was investigated by cyclic voltammetry and chronopotentiogram. The results indicated that the nanoTiO(2)-CNT-PtNi complex catalysts with Pt loading of 0.32 mg/cm(2) exhibited high electrochemically active surface area of 90 m(2)/g and very high electrocatalytic activity and stability for electro-oxidation of methanol. The oxidation peak potential of methanol was 0.67 and 0.44 V at room temperature in atmosphere pressure, respectively, and shifted to 0.64 and 0.30 V at 60 degrees C and the oxidation peak current of methanol was 1.38 A/cm(2). The high electrocatalytic activity and good stability can be attributed to the synergistic catalytic effect of nanocomposite, which leads to the weak adsorption of CO on complex nanostructure catalysts, avoiding poisoning of the catalysts

Recent Advances in Fluorophosphate and Orthosilicate Cathode Materials for Lithium Ion Batteries

Corresponding authors.SHI Zhi-Cong, Email: [email protected]; Tel: +86-411-39893938. YANG Yong, Email: [email protected]; Tel: +86-592-2185753.[中文文摘]综述了用于锂离子电池的氟磷酸盐和正硅酸盐正极材料的研究现状,重点对各种材料的结构及合成方法与性能的关系,特别是对如何改善材料的电化学性能进行了总结和探讨.展望了这两类锂离子电池正极材料的发展趋势.[英文文摘]We review recent research on fluorophosphate and orthosilicate cathode materials for lithium ion batteries.Emphasis is placed on the relationship between structures,methods of preparation and properties of the cathode materials.We especially focus on factors leading to an improvement in their electrochemical performance.Trends of research into fluorophosphate and orthosilicate cathode materials are also discussed.高等学校博士学科点专项科研基金(20090041120020); 中央高校基本科研业务费专项资金(DUT10JN06)资助项

Nitrogen-doped carbon Electrocatalysts for Oxygen Reduction Reaction in Proton Exchange Membrane Fuel Cells

Fuel Cell(FCs) technology, as a new renewable energy generation, has garnered great interest and attention around the world in the past decade because of its advantages such as high power density, environment friendly and so on. Besides, it has the potential to strengthen the national energy security by reducing dependence on petroleum products and offering a cleaner, more efficient alternatives of today energy technology.Fuel Cell(FCs) technology, as a new renewable energy generation, has garnered great interest and attention around the world in the past decade because of its advantages such as high power density, environment friendly and so on. Besides, it has the potential to strengthen the national energy security by reducing dependence on petroleum products and offering a cleaner, more efficient alternatives of today energy technology

Research and developments of electrocatalysts and membranes for proton exchange membrane fuel cells

The research progress in DICP of the electrocatalysts and membranes for proton exchange membrane (PEM) fuel cells will be presented here.The research progress in DICP of the electrocatalysts and membranes for proton exchange membrane (PEM) fuel cells will be presented here

Not Available

Not AvailableNot AvailableNot Availabl

湖泊微拟球藻高含油突变株的构建及筛选

:研宄旨在建立湖泊微拟球藻(iVawzocWoro/w的的遗传转化体系,然后根据外源基因随机插入的特性,挑取抗性转化子构建突变体库,并从突变体库中筛选高含油突变株。以湖泊微拟球藻自身基因启动子和三角褐指藻终止子驱动和终止来源于细菌的WWe抗性选择基因,构建了一个转化载体pPha-Tl-TUB。将线性化后的质粒以电穿孔的方法转化湖泊微拟球藻,通过1Hg/mLzeocin的抗性平板筛选,并经液体培养基连续传代后,得到了可以稳定遗传的转化子。我们从这些转化子中筛选得到了数株油含量高于野生型,且生长也优于野生型的突变株。其中,2个突变株K26和G5的总脂中多不饱和脂肪酸含量更低,其脂肪酸组成更符合作为生物柴油原料的标准。研宄通过随机插入构建突变体库的方法为快速获取优良目的性状的髙产油突变株提供了一个有效手段